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1剑桥雅思8-第三套试题-阅读部分-PASSAGE1-阅读真题原文部分:READINGPASSAGE1Youshouldspendabout20minutesonQuestions1-13whicharebasedonReadingPassage1below.StrikingBackatLightningWithLasersSeldomistheweathermoredramaticthanwhenthunderstormsstrike.Theirelectricalfuryinflictsdeathorseriousinjuryonaround500peopleeachyearintheUnitedStatesalone.Asthecloudsrollin,aleisurelyroundofgolfcanbecomeaterrifyingdicewithdeath-outintheopen,alonegolfermaybealightningbolt'smostinvitingtarget.Andthereisdamagetopropertytoo.LightningdamagecostsAmericanpowercompaniesmorethan$100millionayear.ButresearchersintheUnitedStatesandJapanareplanningtohitback.Alreadyinlaboratorytrialstheyhavetestedstrategiesforneutralisingthepowerofthunderstorms,andthiswintertheywillbraverealstorms,equippedwithanarmouryoflasersthattheywillbepointingtowardstheheavenstodischargethundercloudsbeforelightningcanstrike.Theideaofforcingstormcloudstodischargetheirlightningoncommandisnotnew.Intheearly1960s,researcherstriedfiringrocketstrailingwiresintothundercloudstosetupaneasydischargepathforthehugeelectricchargesthatthesecloudsgenerate.ThetechniquesurvivestothisdayatatestsiteinFloridarunbytheUniversityofFlorida,withsupportfromtheElectricalPowerResearchInstitute(EPRI),basedinCalifornia.EPRI,whichisfundedbypowercompanies,islookingatwaystoprotecttheUnitedStates'powergridfromlightningstrikes.'Wecancausethelightningtostrikewherewewantittousingrockets,'saysRalphBernstein,manageroflightningprojectsatEPRI.Therocketsiteisprovidingprecisemeasurementsoflightningvoltagesandallowingengineerstocheckhowelectricalequipmentbearsup.BadbehaviourButwhilerocketsarefineforresearch,theycannotprovidetheprotectionfromlightningstrikesthateveryoneislookingfor.Therocketscostaround$1,200each,canonlybefiredatalimitedfrequencyandtheirfailurerateisabout40percent.Andevenwhentheydotriggerlightning,thingsstilldonotalwaysgoaccordingtoplan.'Lightningisnotperfectlywellbehaved,'2saysBernstein.'Occasionally,itwilltakeabranchandgosomeplaceitwasn'tsupposedtogo.'Andanyway,whowouldwanttofirestreamsofrocketsinapopulatedarea?'Whatgoesupmustcomedown,'pointsoutJean-ClaudeDielsoftheUniversityofNewMexico.Dielsisleadingaproject,whichisbackedbyEPRI,totrytouselaserstodischargelightningsafely-andsafetyisabasicrequirementsincenoonewantstoputthemselvesortheirexpensiveequipmentatrisk.Witharound$500,000investedsofar,apromisingsystemisjustemergingfromthelaboratory.Theideabegansome20yearsago,whenhigh-poweredlaserswererevealingtheirabilitytoextractelectronsoutofatomsandcreateions.Ifalasercouldgeneratealineofionisationintheairallthewayuptoastormcloud,thisconductingpathcouldbeusedtoguidelightningtoEarth,beforetheelectricfieldbecomesstrongenoughtobreakdowntheairinanuncontrollablesurge.Tostopthelaseritselfbeingstruck,itwouldnotbepointedstraightattheclouds.Insteaditwouldbedirectedatamirror,andfromthereintothesky.Themirrorwouldbeprotectedbyplacinglightningconductorscloseby.Ideally,thecloud-zapper(gun)wouldbecheapenoughtobeinstalledaroundallkeypowerinstallations,andportableenoughtobetakentointernationalsportingeventstobeamupatbrewingstormclouds.AstumblingblockHowever,thereisstillabigstumblingblock.Thelaserisnoniftyportable:it'samonsterthattakesupawholeroom.Dielsistryingtocutdownthesizeandsaysthatalaseraroundthesizeofasmalltableisintheoffing.Heplanstotestthismoremanageablesystemonlivethundercloudsnextsummer.BernsteinsaysthatDiels'ssystemisattractinglotsofinterestfromthepowercompanies.Buttheyhavenotyetcomeupwiththe$5millionthatEPRIsayswillbeneededtodevelopacommercialsystem,bymakingthelasersyetsmallerandcheaper.'IcannotsayIhavemoneyyet,butI'mworkingonit,'saysBernstein.Hereckonsthattheforthcomingfieldtestswillbetheturningpoint-andhe'shopingforgoodnews.Bernsteinpredicts'anavalancheofinterestandsupport'ifallgoeswell.Heexpectstoseecloud-zapperseventuallycosting100,000each.Otherscientistscouldalsobenefit.Withalightning'switch'attheirfingertips,materialsscientistscouldfindoutwhathappenswhenmightycurrentsmeetmatter.Dielsalsohopestoseethebirthof'interactivemeteorology'-notjustforecastingtheweatherbutcontrollingit.'Ifwecoulddischargeclouds,wemightaffecttheweather,'hesays.3Andperhaps,saysDiels,we'llbeabletoconfrontsomeothermeteorologicalmenaces.'Wethinkwecouldpreventhailbyinducinglightning,'hesays.Thunder,theshockwavethatcomesfromalightningflash,isthoughttobethetriggerforthetorrentialrainthatistypicalofstorms.Alaserthunderfactorycouldshakethemoistureoutofclouds,perhapspreventingtheformationofthegianthailstonesthatthreatencrops.Withluck,asthestormcloudsgatherthiswinter,laser-totingresearcherscould,forthefirsttime,strikeback.Questions1-3Choosethecorrectletter,A,B,CorD.Writethecorrectletterinboxes1-3onyouranswersheet.1ThemaintopicdiscussedinthetextisAthedamagecausedtoUSgolfcoursesandgolfplayersbylightningstrikes.BtheeffectoflightningonpowersuppliesintheUSandinJapan.Cavarietyofmethodsusedintryingtocontrollightningstrikes.Dalasertechniqueusedintryingtocontrollightningstrikes.2Accordingtothetext,everyyearlightningAdoesconsiderabledamagetobuildingsduringthunderstorms.Bkills